1. Field of the Invention
The present invention relates to a paper feeding apparatus of a printer, and more particularly, to a paper feeding apparatus of a printer in which paper is stacked at an inclination and supplied to a main body of the printer.
2. Description of the Related Art
In general, a printer includes a paper feeding apparatus to supply a sheet of paper. The paper may be stacked horizontally or at an inclination.
FIG. 1 is a side cross-sectional view illustrating a structure of an ink-jet printer having a conventional paper feeding apparatus, in which paper is stacked at an inclination, and FIG. 2 is a perspective view illustrating the structure of the paper feeding apparatus of FIG. 1.
Referring to FIGS. 1 and 2, a paper feeding tray 20 on which paper P is stacked, is installed on a rear side of a printer main body 10. A sheet of the paper P in the paper feeding tray 20 is supplied to a paper feeding path by a pickup roller 31 and a knock-up plate 22. A knock-up plate spring 28, which elastically biases the knock-up plate 22 upwardly, is installed below the knock-up plate 22. The sheet of the paper P supplied to the paper feeding path, is supplied between a feed roller 40 and a pinch roller 42 via a paper feeding guide 29, and enters into a print zone by driving the feed roller 40. The pinch roller 42 is connected to an end of a pinch roller holder 44, and an other end of the pinch roller holder 44 is connected to a spring 45. The spring 45 presses the pinch roller 42 toward the feed roller 40.
The print zone, where a printing operation is performed on the paper P, corresponds to a printhead 52 of an ink cartridge 50. The ink cartridge 50 is mounted on a carriage return frame 54, and moves perpendicularly to the paper feeding path, along a carriage return shaft 56, by way of a driving unit (not shown). A guide 60, which keeps the paper P flat within the print zone, is installed below the printhead 52. The printed paper P travels along a print path, and is fed between an ejecting roller 62 and a star wheel 64. When the printing operation is completed, the ejecting roller 62 pushes the paper P in a horizontal direction, and ejects the paper P onto an output tray 70.
The paper feeding tray 20 is fixed to the printer main body 10, and a pickup roller driving shaft 33 is rotatably installed perpendicular to the paper feeding path. The pickup roller 31 is rotated by rotation of the pickup roller driving shaft 33. A gear 34 is provided on an end of the pickup roller driving shaft 33 and is driven by a driving unit (not shown).
The paper feeding guide 29 is positioned at a space between a bottom part 21 of the paper feeding tray 20 and the feed roller 40. The paper feeding guide 29 orients the picked-up paper P, so that it feeds horizontally between the feed roller 40 and the pinch roller 42.
But in the paper feeding apparatus having the above structure, when alien substances enter through an opening 11 between the paper feeding tray 20 and the printer main body 10, these alien substances become wedged among the paper feeding guide 29, the feed roller 40, and the pinch roller 42, and thus disturb operation of the printer.
These alien substances may be removed from the printer main body 10 by flipping the printer. But it is not easy to remove them when they are wedged. In addition, they may be removed by disassembling the printer main body 10. It is inconvenient, however, to disassemble the printer main body 10.
Another way to block alien substances is to close an inlet of the opening 11 with an additional cover. However, it is difficult to completely close the opening 11.